Blueberry Swirl Muffins

I was a woman on a mission.

Partially inspired by the big, beautifully empty Moleskine notebook I got myself for Christmas as a brand new recipe book, I've been systematically hunting down and recording all of my best recipes for posterity and for easy transport. But there was one glaring hole: a solid, delicious recipe for blueberry muffins where the blueberries tasted like blueberries and the muffin was moist and enticing. The search, good friends, is over.

I've lately been turning to Cook's Illustrated to get my basic recipes in order. So when I found their recipe for exhaustively tested blueberry muffins, I knew I had to give them a go. And they certainly didn't disappoint. Though there was an extra step (cooking down some of the berries to create a quick jam that is swirled into the batter and baked along with the whole berries) it was easy and provided both a visual pop and a delicious extra kick of berry flavor.

So if you're like me and you're tired of being underwhelmed by tough muffins with watery-tasting blueberries, give these a go. I promise they'll earn a spot in your recipe book, too.

Blueberry Swirl Muffins (from Cook's Illustrated)

Lemon-Sugar Topping: 
1/3 cup sugar, mix with
1 1/2 tsp lemon zest

Muffins:
2 cups blueberries (fresh or frozen; if frozen thaw completely and rinse well)
1 1/8 cups sugar
2 1/2 cups flour
2 1/2 tsp baking powder
1 tsp salt
2 large eggs
4 T butter, melted and cooled slightly
1/4 cup vegetable oil
1 cup buttermilk
1 1/2 tsp vanilla extract

Adjust oven rack to upper-middle position and heat oven to 425 degrees. Spray standard muffin tin with nonstick cooking spray. Bring 1 cup blueberries and 1 teaspoon sugar to simmer in small saucepan over medium heat. Cook, mashing berries with spoon several times and stirring frequently, until berries have broken down and mixture is thickened and reduced to 1⁄4 cup, about 6 minutes. Transfer to small bowl and cool to room temperature, 10 to 15 minutes.

Whisk flour, baking powder, and salt together in large bowl. Whisk remaining 1 1/8 cups sugar and eggs together in medium bowl until thick and homogeneous, about 45 seconds. Slowly whisk in butter and oil until combined. Whisk in buttermilk and vanilla until combined. Using rubber spatula, fold egg mixture and remaining cup blueberries into flour mixture until just moistened. (Batter will be very lumpy with few spots of dry flour; do not overmix.) 

Use large spoon to divide batter equally among prepared muffin cups (batter should completely fill cups and mound slightly). Spoon teaspoon of cooked berry mixture into center of each mound of batter. Using chopstick or skewer, gently swirl berry filling into batter using figure-eight motion. Sprinkle lemon sugar evenly over muffins. 


Bake until muffin tops are golden and just firm, 17 to 19 minutes, rotating muffin tin from front to back halfway through baking time. Cool muffins in muffin tin for 5 minutes, then transfer to wire rack and cool 5 minutes before serving. Enjoy!